Producing metallic silicids.



'niclnllic ores or compouiuls containing silimv IO THOMAS L. WlLLSON, OF OTTAWA, ONTARIO, GANADA.

PFlQDUClNG RIETALMC SILEGEDEE Specification of Letters Patent.

Patented March 12, 1907.

Application filedApril 11, 1904. Serial No. 202,636.

To all w/to'm/ it 711.10g 0/)7L6l'7lb.

llcili known that l, THOMAS L. WILLsQN.

:2 subject of Grout Britain, residing at Ottawa, lrovimrc ol Ontario, (fossils, have invcntall certain new and useful Improvements in .lrmlucing' Mcrollii- SlllClLlas, oi which the following is u SPQC-lllCZLllOll.

This invention rclotos to the treo'lirnent oi or to which silica is o-tlilcd l a. process of snicllii'ig to producc a metallic silicid.

The invention relates particularly to tho treatment of siliooics or sull'icls of nickel, iron, or copper to produce siliciils of thcsc inctuls, cithcr singly or olloycil. I

Tho proccss is choructcrizcd. geucricolly by the troutmcnt or u metallic 'oro or compound by l-ho addition of limo, (or its equivalent,) silica, (if not ulroocly contained in sui'licicnt quonl ityin tho 01-0,) and carbon, nncl subjccb in; the mixture to a sullicionll intense. heat for o sullicient limo to bring about the nccos- SiLI'y rcrluction and reactions. Practically, the heat of the clectric furnace is essential, and. whcrc l spool; of clcctrosn'iolting l l l i l l l J 1i is to be understood that I refer to snieliing at a temperature materially above ordinary furnacc temperatures and such can be ti mined practically only in electric furnaces. ll i'ho ore contains sulfur, proportions/lely greater quantity of lime is required: The resuliin productis :1. silicid oi" the metal or metals 0'1? the ore or coinpouiul. Thus with s nickel ore the product is a nickel SlllCld, and with a nickel-iron oro it is 21f="ll'O-11l.C-l@l l silicid. The remaining products ol the roac tions arc either volotilizccl. or discharged as slo AS one illustration of the practice of my invention I will. take the case of nickel sulfid to which is orldccl lime, silica, and. capbon in suitable proportions, the mixture boing heated in on cl -ctric furnace, thereby reducing the lime and silica, the calcium combining With tho sulfur of the nickel sulfid and forming calcium suliid, Which'lloats as o slag, and the silicon uniting mainly with the nickel. to form nickel .silioid. As another illustration .i may mention the application of my process to the recovery ofiron from the worthless-form of iron silicate containing sulfur, which is now a waste product in" the reduction of nickel-sulfid ores. This materi'ul contains alread a large percentage of silica, so that itis unnecessary to add silica, I add l a suitable proportion of lime and carbon and smelt in the olcclric furnace, producii'ig calcium sulicl, which floats oil, and iron silicid. If the iron silicate contains nickel, this will appear in corresponding proportion in the resul lingsilicid.

My invcnl ion is valuable in its application to nickel o n (l iron sullicl ores, which orcs con tain usually small proportion of copper.

With such orcs I add a suitable. proportion of 6 lin'iestonc, silica, and. carbon. If this mixture u'c'rc sincltecl in :1 blzist-iurnzico, there would rcsult :1. calcium silicate of iron and a 'lllCliQlflPPtl' motto; but by the more sc- Li'vo reduction obtainable by electric smelt ing, calcium and silicon are freed, the cal-- cium uniting with the sulfur of like ore and. "forming calcium suliiil, which limits oil", and. the silicon uniting with tho nickel and iron forming a lorro-niclqcl silicid. silicon iiilso combines with the sulfur to form silicon suliiil. which is volatile.

'lheoretically, the required proportions should be obtainable thus: Enough lime or limcstone sl'ioulil be added, calculated to (his, to combine with the total sulfur in the ore. Enough silicosliould be added to form with the calcium equivalent thus detcrn'iined CnOCSiOQ, 'lhon enough carbon should he added lo liberate from. the calcium silicate lilac calciun': :in-zl silicon, the former uniting with tho sulfur and the latter with the iron and nickel. in practice, howcver, it is found with sull'iil that a considerably smaller proportion of limo, silica, and carbon than theoretically indicated may be successfully used. For example, in an electric furnace using about thirty-live volts and four thousand ai nperes the process has been successfully practiced with onlyholl tho theoretical proportions of lime, silica, and. carbon. This is probably explsinoble by the action of the intense heat of the furnace in dissociating sulfur, 'W'lL'lCll lS vol ntilized and driven co and coulkil. doubtless be recovered as n. by- 100 product.- Probably this effect would be oven gr-sstor with. a. larger electric furnace generating greater hoot.

For theiguidonce of those skilled in the art I will give in. detailgtlio. results obtained in 103 operating with. a. ferro-nickel-suliid ore of-the following; proportions, namely: iron, fortyfour to forty-sight per cent; nickel, four to seven. per: cent; copper, one to two per cent;

sull'i r, t realty-six to twenty-eight per cent.; 1

Some of the 7 The ferro-nickcl silicid obtained by my process is chiell y useful in the production of nickel steel. F or this purpose iron may be added. in order to reduce the nickel to'thc seven pounds of granulated coke. Mix these well together and feed gradually into a \Nilh i son electric arc furnace in the same manner as in the manufacture of calcium, carbid.

Energizing the furnace with thirty-live to thirty-seven volts and four thousand amperes, the reduction of this quantity of material will require from two to three hours, if startedcold. silicid has analyzed as follows: iron, 75.6 per cent. nickel, 9.4 per cent. silicon, 12.46 per desired proportion, which may be done 7c either in the electric furnace or as a subscqucnt process, after which the silicon is eliminated by bossemerizing.

. It is .to be understood that in the practice of my process limestone may be used instead of lime, or magnesia, (m the form of dolomite,

, for cxample,) or any otherbasic compound, as

an oxid of an alkaline earth metal may be The resulting ferro-nickel 1 1 .(or limestone) being preferable to other comper cent; sulfur, .635 per cent; copper, .76 l per cent; unascertamed impurities, 1.145

per cent; total, 100,000.

In running continuously, since the calcium sullid remains in the furnace when the silicid is tapped oil, the quantity of lime or limestone used may be greatly diminished after I the first few hours, the proportion of sand being correspondingly increased, thereby cheapening the process.

For. the more complete elimination of the sulfur the heat of the electric furnace may be increased, or the proportion of silica may be increased, or fiuor-spar may be added, preferably shortly before tapping off the product, introducing it preferably witha blast of air through twyers.

Except for its greater cost, fluons r (calcium iluorid) might be used to W10lly or partly replace the lime or limestone.

My process is advantageously applicable in connection. with ores in the nature of silicates of iron, nickel, and magnesium, such as those known as new Caledonian ores. To reduce such an ore, I add lime (or its equivalent) and carbon in. suitable proportions. Ordinarily such ores contain su'llicient silicon in the form of silicate, so that the addition of silica is unnecessary. The proportion of lime required may be diminished according to the proportions of magnesium contained in the ore. In the case of an orc containing an exceptionally large proportion of magnesium, due to its containing little or nofl're'e silica, the proportion, of lime required may be reduced to theminimum. The proportion of carbon required is that which is required to combine with the oxygen compounds comprised in-the ore. On clectrosmelting such a mixture the reduction of the ore liberates iron, nickel, silicon, magnesium, and calcium, the silicon forms with the n'ictals a ferromickel silicid, the calcium and magncsium combine with. any impurities such as oxygen or oxygen compounds or the like rcmannng m the mass and separate as a slag.

from time to time arid is obtained in a substai'itially, pure state.

additional substances in the product;

substituted as the equivalent of lime, lime pounds of this class because of its cheapness.

When I speak of treating a compound containing nickel or any other specific ele mcnt or elements, it will be understood that I do not thereby exclude the idea of the compounds containing other elements besides the one or more specifically stated. Likewise, when I speak of producing a nickel silicid or other specific product it will be undcrstood that I do not thereby exclude thcidea of producing at the sametime other products than that specifically expressed. Dcpend- V ing upon the presence or absence of other'elements in the original com ound than those stated, we may expect to 1nd or not to find The invention is applicable Without variations in the processto original materials of various compositions and to obtain products correspondingly varying. I v

The compounds referred to are either natural (ores) or artificial and may contain other impurities than those specifically mentioned.

The processes described in so far as they relate to sulfids are included only generically in-the claims of this part, specific claims there for being presented in a divisional application, Serial No. 341,091, filed November 5, 1906. i 1 IO What I claim is 1. 'lreating a compound containing sulfur, nickel, iron, silicon, and oxygen, by electrosmelting with lime and carbon and additional silica and finer-spar, to combine with all sulfur, oxygen and other impurities,'and to re-' cover a-compound of iron, nickel andsilicon, and bessemerizing to burn out the silicon and leavo'a compound of iron and nickel.

Treating a compound,containingnickel x 9 and silicon with oxygen, sulfur or other impurities, by electrosmelting it with a basic compound and carbon, in such proportions as to combine with. all oxygen, sulfur, or other impurities, and produce a nickel silicid.

3. Treating a compound containing nickel I j and silicon and im purities by clectrosmelting The form-nuke] sllnid may be tap 'ied oil with lime and carbon to prodln-c a nickel sili i cid, the lime combining with the impurities.

silicate and impurities by,-. electrosmelting with a basic compoun'd-and carbon, to produce a nickel silicid, the lime combining with the impurities.

5. Treating a compound containing iron, nickel and silica, by electrosmelting it with a basic compound and carbon, to produce a ferro-silicid.

6. Treating a compound containing nickel and iron, by electrosmelting with a basic compdundysilica, and carbon, to produce a ferro-nickel silicid, and bessemerizing to burnout the silicon and form nickel-steel.

7; Treating a compound containing nickel and silicon, by electrosrnelting with a basic compound and carbon, to produce a nickel' silicid, and bessemerizing to burn out the silicon and produce nicke 8. Treating a compound containing nickel and silicon, by clectrosmelting it with a basic compound and carbon, to produce nickel silicid, and introducing fiuor-spar into the molten product and bessemcrizing to burn out the silicon and form nickel.

In witness whereof I have hereunto signed my name in the presence of two subscribing Witnesses.

THOMAS L. WILLSON.

Witnessesz EUGENE G. MYERS, FRED WHITE. 

